Machine of the centrifugal type



Oct. 19, 1954 B. c. GROSSKOPF 2,691,944

MACHINE OF THE CENTRIFUGAL TYPE Filed Sept. 12, 1950 BRUNO. CARL GROSSKOPF' 46 ATTORNEY Patented a. 19, 1954 MACHINE OF THE CENTRIFUGAL TYPE Bruno Carl Grosskopf, Hamburg-Gr. Flottbek, Germany Application September 12, 1950, Serial. No. 184,376

Claims priority, application Germany January 2, 1950 My invention relates to machines of the centrifugal type, such as pumps, compressors and the like, for liquid or gaseous media. The invention has, inter alia, for its object to provide a machine of this type, which for a certain power consumption is of smaller dimensions than the constructions hitherto used. Another object of the invention is to provide a machine, such as a pump, which for a certain consumption of energy is subjected to smaller strains on the external members of the housing on the pressure side of the machine, and wherein the mounting of the rotating parts may be effected by simpler means than was previously the case. A further object of the invention is to provide a machine, such as a pump, which is distinguished by an emciency. A still further object is to provide a machine having reduced external losses, that is in the packing box and by wheel friction, as well as interior losses which are to be understood as the fiow losses in the pump wheel channels connecting the latter.

Further objects and advantages of the invention will be apparent from the following description considered in connection with the accompanying drawings, which form a part of this specification, and of which:

Fig. 1 is a longitudinal sectional view of one embodiment of the invention; and

Fig. 2 is a similar view of another embodiment.

Equivalent parts are designated by the same reference characters in the various figures.

In Fig. 1, I0 designates the pump shaft, which is mounted in a bearing I2. The shaft carries a pump wheel It provided with a rim of blades I6, said wheel being herein referred to as the primary wheel. The primary wheel has an intake passage I8 extending axially and radially outwardly from the stationary inlet 20, said passage being bounded toward the shaft by a hub cap 22 imparting to said intake passage a shape which is advantageous from the point of view of streamline flow. The blades I likewise extend axially and radially outwardly and terminate in an annular space 24 in the stationary pump housing 26.

A second pump wheel 28, here called the secondary wheel, is provided with a rim of blades 30 and is rigidly connected to the pump Wheel I4 carrying the same. The place of attachment of this wheel is axially displaced relative to the blades it of the primary wheel and is located at the exterior side of the inlet portion of this pump wheel. The passage of flow of the secondary wheel 28 and the blades 30 thereof are obliquely 3 Claims. (Cl. 103108) 2v disposed, but so as to. extend axially outwardly in a direction opposed to that of the blades IS. The inlet side of the secondary wheel and the annular chamber 26 are interconnected by an annular passage 32, in which may be provided a guide blade rim 34 carrying a partition 35. The fluid flows, as indicated by the arrows, that is to say radially outwardly in the blade rim I6, radially inwardly in the annular passage 32, and then again radially outwardly in the blade rim 30, whereupon the fluid enters a discharge spiral 36, guide blade system, difl'usor ring or the like in the pump housing 20. Either one or both of the blade wheels may be provided with apertures 38 to equalize the pressure relative to the surrounding spaoes wherein the wheels rotate. Furthermore, packings 40, 42 are arranged in the ordinary manner between the movable and stationary members of the pump.

According to the invention, the pump has, in comparison with a single-stage pump of the same capacity, smaller radial dimensions, a matter which has a favourable effect on the strains to be taken up by the bolt bonds in the stationary housing. The path of flow of the operating fluid becomes shorter than in a multi-stage pump of conventional construction, the changes of direction of the fluid softer, the frictional losses being thus reduced and the efiiciency improved in a corresponding degree. As will appear from Fig. 1, the discharge edges of the two blade rims I6 and 30 may be located on the same or approximately the same radius, while the blades 30 have a smaller radial extension.

The housing of the pump shown in Fig. 2 consists of three main parts, viz. an intermediate member I02 and two end members I04 and I06, the latter being connected to the intermediate member by screw bonds I05 and I01, respectively, and sealed against the same as at I09. To the intermediate member the partition and the guide blade system 34 are secured. Moreover the discharge spiral or the like 36 is provided in said member. The end member I04 has a pipe socket I00 forming the inlet channel 20. Disposed between the end member I06 and the intermediate member I02 are the primary wheel I4 and the annular chamber 24. The end member I 06 of the housing extends to the shaft I0 where it encloses a sealing box H0. The housing consisting of the members I02, I04 and I06 is carried with the aid of screws IIZ by a frame II4 which is provided with a bearing housing II6 including two bearings HR for journalling the shaft I0. The primary wheel and the secondary wheel 28 carried by the same as well as the annular channel 32 are in this embodiment adapted to be traversed by the operative fluid in radial or substantially radial direction.

While two more or less specific embodiments of the invention have been shown, it is to be understood that this is for purpose of illustration only, and the invention is not to be limited thereby, but its scope is to be determined by the appended claims.

What I claim is:

1. A centrifugal pump comprising a casing and a rotor mounted for rotation in said casing, said rotor comprising a primary wheel portion providing a ring of primary blades and a secondary wheel portion carried by said primary portion and providing a ring of secondary blades, said casing having a central inlet for axial admission of fluid to said primary wheel portion in a given direction and guide means for conducting fluid discharged from said primary wheel to the inlet of said secondary wheel, said ring of secondary blades being located axially on the inlet side of said ring of primary blades and. around said central inlet, and said guide means and said ring of secondary blades being arranged to provide for flow of the fluid therethrough in a path around said. inlet in a direction the axial component of which is opposite that of said given direction.

2, A centrifugal pump having a casing, a rotor rotatably mounted in said casing, a fluid outlet in said casing, a fluid inlet in said casing disposed axially of said rotor, said rotor having primary blades extending substantially radially thereof and secondary blades axially spaced from said primary blades towards said inlet and disposed substantially radially of said rotor, fluid conducting channels in said casing communicat ing with the discharge from said primary blades and with the inlet to said secondary blades, said 4 channels being arranged to conduct fluid from said primary blades to said secondary blades progressively in a direction having an axial component directed toward said inlet, and means connecting the discharge of said secondary blades with said outlet.

3. A centrifugal pump comprising a casing having a central section and two end sections removably secured thereto, a rotatably mounted shaft extending axially through a first one of said end sections, a rotor comprising a primary Wheel having substantially radial primary pump blades mounted on said shaft in overhung relation within the central section of the casing, a secondary wheel having substantially radial secondary pump blades carried by said primary wheel within the central section of the casing, the second one of said end sections providing a fluid inlet coaxial with said rotor, said primary blades being adjacent to said first end section, said secondary blades being adjacent to said second end section, said central section providing connecting means for flow of fluid from the discharge of said primary wheel to the inlet of said secondary wheel and said casing providing an outlet for the discharge from said secondary Wheel.

References Cited in the file of this patent UNITED STATES PATENTS 

